Air filter with serviceable filter media

Abstract

An air filter element has a cylindrical filter media sleeve axially slidable along and around an inner liner from either axial end of the sleeve. First and second end caps at distally opposite axial ends of the liner and sleeve each have a central aperture, the aperture in the first end cap providing air flow therethrough in communication with the hollow interior of the liner, the aperture in the second end cap retaining a closing cover. The cylindrical filter media sleeve extends axially along the inner liner and is axially retained between the cover and the first end cap. The cover is removably mounted to the second end cap in snap-in relation and axially retains the sleeve on the inner liner.

What is claimed is:  
     
       1. An air filter element comprising a cylindrical inner liner pervious to air flow and extending axially along an axis between distally opposite first and second axial ends and having a hollow interior, first and second distally opposite end caps each permanently mounted to said inner liner at said first and second ends, respectively, said first end cap having a central aperture providing air flow therethrough in communication with said hollow interior, said second end cap closing said hollow interior, filter media comprising a removable and serviceable cylindrical sleeve extending axially between distally opposite first and second axial ends and axially slidable along and around said inner liner from either of said first and second axial ends of said sleeve. 
     
     
       2. The invention according to  claim 1  wherein said sleeve is open at each axial end and has an inner diameter at each axial end permitting axial sliding of each of said axial ends of said sleeve along said inner liner. 
     
     
       3. The invention according to  claim 2  wherein said filter element in combination with said sleeve comprises two installation modes, comprising a first mode with said first axial end of said sleeve axially slid past said second end cap and along said inner liner, and a second mode with said second axial end of said sleeve axially slid past said second end cap and along said inner liner. 
     
     
       4. The invention according to  claim 3  comprising a cover removably mounted to said second end cap and engaging one of said axial ends of said sleeve and axially retaining said sleeve, said sleeve having an inner surface facing radially inwardly towards said liner, and having an outer surface facing radially outwardly and spaced radially outwardly of said inner surface, said cover having an annular rib engaging said outer surface of said sleeve and extending axially therealong. 
     
     
       5. The invention according to  claim 3  comprising a cover removably mounted to said second end cap and engaging one of said axial ends of said sleeve and axially retaining said sleeve, said sleeve having an inner surface facing radially inwardly toward said inner liner, and having an outer surface facing radially outwardly and spaced radially outwardly of said inner surface by a given radial dimension, said cover having a pair of annular ribs extending axially toward said first end cap comprising a first rib engaging said inner surface of said sleeve and extending axially between said inner liner and said inner surface of said sleeve, and a second rib spaced radially outwardly of said first rib by said given radial dimension and engaging said outer surface of said sleeve and extending axially therealong. 
     
     
       6. The invention according to  claim 1  comprising a fence secured to said inner liner and having a first flange extending radially outwardly from said inner liner between said sleeve and said first end cap, and a second flange extending axially from said first flange toward said second end cap along the outside of said sleeve. 
     
     
       7. An air filter element comprising a cylindrical inner liner pervious to air flow and extending axially along an axis between distally opposite first and second axial ends and having a hollow interior, first and second distally opposite end caps mounted to said inner liner at said first and second ends, respectively, each end cap having a central aperture, the aperture in said first end cap providing air flow therethrough in communication with said hollow interior, the aperture in said second end cap retaining a closing cover, said cover being removably mounted to and engaging the exterior of said second end cap, filter media comprising a cylindrical sleeve extending axially along said inner liner and axially retained between said cover and said first end cap. 
     
     
       8. The invention according to  claim 7  wherein said cover is removably mounted to said second end cap at said aperture in said second end cap. 
     
     
       9. The invention according to  claim 8  wherein said second end cap closes said hollow interior at said second end of said inner liner, with said cover closing said aperture in said second end cap. 
     
     
       10. The invention according to  claim 9  wherein said first end cap has a radial thickness between inner and outer diameters, said inner diameter defining said aperture in said first end cap and being substantially the same as the diameter of said inner liner. 
     
     
       11. The invention according to  claim 9  wherein said second end cap has a radial thickness between inner and outer diameters, said inner diameter defining said aperture in said second end cap, said outer diameter being substantially the same as the diameter of said inner liner. 
     
     
       12. The invention according to  claim 9  wherein said sleeve has a radial thickness between inner and outer diameters, and wherein said cover extends radially outwardly beyond said second end cap by a radial dimension substantially equal to said radial thickness. 
     
     
       13. The invention according to  claim 9  wherein said first end cap has a radial thickness between inner and outer diameters, said inner diameter defining said aperture in said first end cap and being substantially the same as the diameter of said inner liner, said second end cap has a radial thickness between inner and outer diameters, said inner diameter of said second end cap defining said aperture in said second end cap, said outer diameter of said second end cap being substantially the same as the diameter of said inner liner, said sleeve has a radial thickness between inner and outer diameters, and wherein said cover extends radially outwardly beyond said second end cap by a radial dimension substantially equal to said radial thickness. 
     
     
       14. The invention according to  claim 9  comprising a fence secured to said inner liner and having a first flange extending radially outwardly from said inner liner between said sleeve and said first end cap, and a second flange extending axially from said first flange toward said second end cap along the outside of said sleeve. 
     
     
       15. An air filter element comprising a cylindrical inner liner pervious to air flow and extending axially along an axis between distally opposite first and second axial ends and having a hollow interior, first and second distally opposite end caps mounted to said inner liner at said first and second ends, respectively, said first end cap having a central aperture providing air flow therethrough in communication with said hollow interior, said second end cap closing said hollow interior, filter media comprising a cylindrical sleeve extending axially between distally opposite first and second axial ends and axially slidable along and around said inner liner, a cover removably mounted to said second end cap in snap-in relation and axially retaining said sleeve on said inner liner. 
     
     
       16. The invention according to  claim 15  wherein said sleeve is axially retained between said first end cap and said cover. 
     
     
       17. The invention according to  claim 15  wherein said cover radially retains said sleeve outwardly of said liner. 
     
     
       18. The invention according to  claim 17  wherein said cover has a rib extending axially along the outside of said sleeve and retaining said sleeve outwardly of said liner. 
     
     
       19. The invention according to  claim 17  wherein said cover has a first rib extending axially between said sleeve and said inner liner, and a second rib spaced radially outwardly of said first rib and extending axially along the outside of said sleeve, wherein said cover radially retains said sleeve outwardly of said liner by retaining said sleeve between said ribs. 
     
     
       20. The invention according to  claim 15  wherein said cover is inserted axially onto said second end cap in said snap-in relation. 
     
     
       21. The invention according to  claim 20  wherein said second end cap has an aperture therethrough, and wherein said cover has a shank extending axially toward said first end cap, said shank having a detent received in said aperture in said second end cap in snap-fit relation. 
     
     
       22. The invention according to  claim 21  comprising a resiliently compressible sealing grommet in said aperture, and wherein said detent comprises a raised shoulder on said shank compressing said grommet as said cover is inserted axially onto said second end cap, said shoulder snapping-in behind said grommet in said hollow interior. 
     
     
       23. A method for servicing an air filter element by replacing filter media, comprising providing an air filter element having a cylindrical inner liner pervious to air flow and extending axially along an axis between distally opposite first and second axial ends and having a hollow interior, providing first and second distally opposite end caps each permanently mounted to said inner liner at said first and second ends, respectively, providing said first end cap with a central aperture providing air flow therethrough in communication with said hollow interior, providing said second end cap closing said hollow interior, providing filter media comprising a cylindrical sleeve extending axially between distally opposite first and second axial ends and axially slidable along and around said inner liner from either of said first and second axial ends of said sleeve, 
       servicing said air filter element by removing said filter media sleeve when dirty by axially sliding said sleeve along said inner liner, and replacing the dirty filter media sleeve with a clean filter media sleeve by inserting said clean sleeve onto said inner liner from either axial end of said sleeve and axially sliding said sleeve along said inner liner.  
     
     
       24. The method according to  claim 23  comprising cleaning the removed dirty filter media sleeve to provide a cleaned filter media sleeve, and providing said cleaned filter media sleeve as said clean sleeve and inserting same back onto said inner liner, to enable re-use of said filter media sleeve. 
     
     
       25. The method according to  claim 23  wherein said sleeve is open at each axial end and has an inner diameter at each axial end permitting axial sliding of each of said axial ends of said sleeve along said inner liner. 
     
     
       26. The method according to  claim 25  wherein said filter element in combination with said sleeve comprises two installation modes, comprising a first mode with said first axial end of said sleeve axially slid past said second end cap and along said inner liner, and a second mode with said second axial end of said sleeve axially slid past said second end cap and along said inner liner. 
     
     
       27. The method according to  claim 26  comprising providing a cover, and removably mounting said cover to second end cap to engage one of said axial ends of said sleeve and axially retain said sleeve, servicing said air filter element by removing said cover from said second end cap prior to removal of said sleeve from said inner liner, and then inserting said clean sleeve onto said inner liner and then mounting said cover to said second end cap, providing said sleeve with an inner surface facing radially inwardly toward said inner liner, and an outer surface facing radially outwardly and spaced radially outwardly of said inner surface, providing said cover with an annular rib engaging said outer surface of said sleeve and extending axially therealong, and comprising mounting said cover to said second end cap to retain said sleeve radially between said rib and said inner liner and axially between said cover and said first end cap. 
     
     
       28. The method according to  claim 26  comprising providing a cover, and removably mounting said cover to said second end cap to engage one of said axial ends of said sleeve and axially retain said sleeve, servicing said air filter element by removing said cover from said second end cap prior to removal of said sleeve from said inner liner, and then inserting said clean sleeve onto said inner liner and then mounting said cover to said second end cap, providing said sleeve with an inner surface facing radially inwardly toward said inner liner, and an outer surface facing radially outwardly and spaced radially outwardly of said inner surface by a given radial dimension, providing said cover with a pair of annular ribs extending axially toward said first end cap, including a first rib engaging said inner surface of said sleeve and extending axially between said inner liner and said inner surface of said sleeve, and a second rib spaced radially outwardly of said first rib by said given radial dimension and engaging said outer surface of said sleeve and extending axially therealong, and comprising mounting said cover to said second end cap to retain said sleeve radially between said ribs and axially between said cover and said first end cap. 
     
     
       29. The method according to  claim 23  comprising retaining the axial end of said sleeve at said first end cap by providing a fence secured to said inner liner and having a first flange extending radially outwardly from said inner liner between said sleeve and said first end cap, and a second flange extending axially from said first flange toward said second end cap along the outside of said sleeve. 
     
     
       30. The method according to  claim 23  comprising providing an aperture in said second end cap, and removably mounting a cover to said second end cap at said aperture to axially retain said sleeve along said inner liner between said cover and said first end cap. 
     
     
       31. The method according to  claim 30  comprising closing said hollow interior at said second end of said inner liner with said second end cap, and closing said aperture in said second end cap with said cover. 
     
     
       32. The method according to  claim 23  comprising removably mounting a cover to said second end cap in snap-in relation and axially retaining said sleeve on said inner liner. 
     
     
       33. The method according to  claim 32  comprising providing said cover with an axially extending rib, and mounting said cover to said second end cap in said snap-in relation such that said rib extends axially along the outside of said sleeve and retains said sleeve outwardly of said liner. 
     
     
       34. The method according to  claim 32  comprising providing said cover with first and second axially extending ribs radially spaced from each other, and mounting said cover to said second end cap in said snap-in relation such that said first rib extends axially between said sleeve and said inner liner, and said second rib extends axially along the outside of said sleeve, such that said cover radially retains said sleeve outwardly of said liner by retaining said sleeve between said ribs. 
     
     
       35. The method according to  claim 32  comprising installing said cover by inserting same axially onto said second end cap in said snap-in relation. 
     
     
       36. An air filter comprising a cylindrical inner liner pervious to air flow and extending axially along an axis between distally opposite first and second axial ends and having a hollow interior, first and second distally opposite end caps mounted to said inner liner at said first and second ends, respectively, said first end cap having a central aperture providing air flow therethrough in communication with said hollow interior, said second end cap closing said hollow interior, filter media comprising a cylindrical sleeve extending axially between distally opposite first and second axial ends and axially slidable along and around said inner liner, a cover removably mounted to said end cap in snap-in relation and engaging the exterior of said end cap and axially retaining said sleeve on said inner liner.